1. Field of the Invention
This invention relates to agriculture residue based panel or compressed shape materials, such as an absorbent panel or environmentally safe nursery pots. Agriculture residues include, but are not limited to, corn residues, wheat straw, rye, barley, prairie grasses, alfalfa straw, or flax straw. More particularly, this invention relates to corn residues which are processed and admixed with a variety of adhesive materials to provide materials which encompass multiple consumer uses.
2. Description of the Prior Art
It is well known that cellulose fibers are good absorbents for soluble oils, water and water based fluids and even heavy oils.
Clay products have been widely used as absorbents, but present problems both in dispersion and disposal upon usage in hazardous waste clean up, including oil spills. Clay products typically are supplied in granular form and thus are difficult to control upon dispersion on an oil spill area and are also difficult to collect and dispose of once the clean up has completed. The introduction of cellulose based products has added BTU value to the sorbent product, thus adding avenues of disposal of the spent sorbent material by incineration.
Readily available plant celluloses such as wood and rice hulls reduced to a powder can be processed into absorbent products. Processing corn cobs to produce an absorbent material is also known.
U.S. Pat. No. 3,617,564 to Vander Hooven, describes "a method for removing oil or oily substances from the surface or upper layer of a body of water, comprising spreading an absorbent, consisting essentially of corn cob components, excluding all but trace amounts of the woody ring component" upon the oil. Vander Hooven is directed to corn cob component separation such that the lighter cob components are then spread on the water surface without danger of absorbing great amounts of water and then sinking beneath the water's surface after also absorbing hazardous materials.
U.S. Pat. No. 4,497,712 to Cowling discloses "a pillow" which contains corn cobs, having an absorption capacity in excess of 300% to 500%, and which have been ground into granules. The granules in Cowling must also be light weight, such as 14 lbs. per cubic foot so that the pillow will float when saturated. Thus, Cowling necessarily requires that woody ring separation in order to form a light weight absorbent material.
U.S. Pat. No. 5,062,954 to Leedy et al. discloses a cellulose based product and method of manufacture, wherein the cellulose source is corn cob components. Specifically, Leedy requires the use of the corn cob lighter components of chaff and pith, which must be separated from the hard woody ring. The absorbent material in Leedy can contain no more than about 5% of the woody ring, which comprises up to about 60% of corn cob weight. Further, Leedy requires processing of the light corn cob components to a particle size preferably in the range between a number 10 screen and a number 60 screen size.
U.S. Pat. No. 5,160,629 to Brown discloses method for using entire corn cobs for absorbing oil spills, such that the cobs do not sink. Brown requires removal of all kernels from whole corn cobs, and preferably completely drying the corn cobs prior to application on an oil spill.
Further, composition boards known in the art such as particle board, oriented strand board, medium density fiber board and plywood are typically evaluated by mechanical characteristics such as static bending, evaluated as modulus of rupture and modulus of elasticity, internal bond, water absorption and thickness swell. However, no mention is made regarding board sorbency qualities.